Universal snake bite cure may be possible

An antivenom that protects against all deadly snake bites could be on the horizon due to a breakthrough by British scientists.

Researchers at the Liverpool School of Tropical Medicine say they are one step closer to a wonder drug that would allow doctors to treat victims without knowing what kind of snake has bitten them.

More than 125,000 people die every year due to snake bites around the world, with a universal antivenom saving a huge number of lives.

The World Health Organization this year added snakebite to its list of neglected tropical diseases, with the true number of people who are killed likely being much higher as some countries do not keep accurate records.

The venom specialists in Liverpool have shown it is possible to treat a bite from one snake with antivenom produced from a completely different species.

‘Provides a basis for looking at antivenom in a new way’ 

In particular, they identified an antivenom produced from the saw-scaled viper, one of south Asia’s, and the world’s, most dangerous snakes.

In lab experiments on blood and mice, the same antivenom worked on a potentially lethal amount of venom from the boomslang snake; a very distant relative of the saw-scaled viper.

Lead author of the study Dr Stuart Ainsworth said: ‘This work is extremely exciting and we hope it provides a basis for looking at antivenom in a new way.

‘Traditionally, when producing an antivenom that could treat the bite of many different snakes, we have done so from a geographical standpoint.

‘However, we have now shown that it may be of more benefit to allow clinicians an opportunity to treat the symptoms they see without having knowledge of the exact species of snake involved.’

What is snake venom and how is it treated? 

Snake venom is a white or yellow-coloured liquid that is produced in glands behind the eyes and pumped down a duct to the fangs when it bites down on something or someone.

The fangs act like a hypodermic needle, injecting the venom quickly and efficiently into the victim.

Snakes with fangs at the front of their mouths are most dangerous, for example the cobra, puff adder, viper, rattlesnake and mamba.

Antivenoms are usually made for a specific snake and only work if someone is bitten by the same animal that supplied the venom to make the antidote.

Historically, they are also made with the venoms of snakes from a single region.

This means there is a need for many different antivenoms across different parts of the world.

Could make antivenom more affordable 

Rather than looking at the problem geographically, the team in Liverpool instead decided to focus on the symptoms caused by a large number of different venoms.

These fall broadly into four categories that either attack the circulatory or the nervous system.

Categories include coagulopathy, or abnormal blood clotting; haemorrhaging; neurotoxicity, which damages the nervous system causing paralysis; and cytotoxicity, where the bite kills cells and destroys tissue.

The team, whose findings are published in Communications Biology, discovered some antivenoms could prevent blood clotting caused by more than one kind of snake.

The hope is to progress this research further to find out if the same thing could be done to combat the different effects caused by different venoms.

The study’s senior author Dr Nick Casewell said: ‘Each geographic area has huge diversity in the types of venomous snakes that cause different pathologies.’

He said that proving it could be done for one type of effect should mean they could do the same thing for the other types of venom for snakes across the world.   

Dr Casewell added the science could ‘make snakebite treatments more affordable for the impoverished victims of the tropics who suffer the greatest burden of snake bite.’